Optimized routing of a call to a roaming subscriber

ABSTRACT

System for mobile telecommunication, comprising a first mobile network (KTm), connected to a first nonmobile network (KTv) having routing means (X). Terminals connected to the nonmobile network may set up a connection with mobile terminals having the first or a second mobile network as their home network. A mirror register (MLR), connected to the routing means in the nonmobile network, is used to record a copy of the user profile transferred by the HLR register of the home network of a roaming mobile terminal to the VLR register of the non-home network. The user profile stored in the mirror register in this manner is then used—together with the VLR—to directly drive the routing means X of the nonmobile network KTv, as a result of which the routing path is considerably shortened.

BACKGROUND OF THE INVENTION

The invention relates to a system for mobile telecommunication,comprising a first network arranged for mobile telecommunication—thefirst mobile network—, connected to a first network arranged fornonmobile telecommunication—the first nonmobile network—, suitable forsetting up connections between, on the one hand, terminals whoseconnections are routed by way of routing means within the firstnonmobile network, and, on the other hand, terminals whose connectionsare routed using registers within the first mobile network or registerswithin a second network arranged for mobile telecommunication—the secondmobile network—, a first register in both mobile networks comprisinginformation relating to mobile terminals having the first or second, asthe case may be, mobile network as a home network, and a second registercomprising information relating to mobile terminals which, irrespectiveof their home network, make use of the first or second mobile network,respectively, while, if a terminal having the first mobile network asits home network wants to make use of the second mobile network, thesecond register of the second mobile network receives a user profilefrom the first register of the first mobile network, comprising systemdata relating to the user of said terminal. The above relates to thecase in which a terminal having the first mobile network as its homenetwork, wants to make use of the second mobile network. The invention,however, also relates to the inverse situation, namely, that a terminalhaving the second mobile network as its home network, wants to make useof the first mobile network. In said inverse situation, the secondregister of the first mobile network receives a user profile from thefirst register of the second mobile network. It is known that a call toa mobile terminal (“mobile user”) abroad (i.e., outside the range of itshome network), is first routed to the home network. Then, it is reroutedfrom the home network to the destination network, where theuser/terminal is located. For the inverse situation, the sameapplies—mutatis mutandis. All of this implies a long routing path forthis kind of call. This results in additional costs (an interconnectiontwice), a more extensive connection-buildup time and a deterioratedspeech quality, since a longer path has to be covered.

SUMMARY OF THE INVENTION

The object of the invention is to overcome said drawbacks.

For this purpose, the invention provides for a telecommunication systemof the aforementioned kind, which system, according to the invention,comprises a mirror register connected to the routing means in the firstnonmobile network in which, under control of control means, a copy ofthe user profile given off by the first register of the first mobilenetwork is received and recorded, for routing a call from the firstnonmobile network to said mobile terminal making use of the secondmobile network having the first mobile network as its home network, thecontrol means extracting routing information for the routing means ofthe first nonmobile network from the user profile recorded in the mirrorregister associated with (the user) of said terminal.

The core of the invention consists of the application of a mirrorregister (Mirror Location Register) in the immediate vicinity of therouting means of the nonmobile network. According to the invention, acopy of the user profile of the user of the mobile terminal istransmitted from the first register—the “Home Location Register”(HLR)—of the mobile network to the mirror register and recorded there.The contents of the user profile is then used by the routing means ofthe nonmobile network—connected to the mirror register—for routing callsfrom the nonmobile network to the mobile terminal in a much more directmanner than is the case according to the prior art.

Preferably, the routing information extracted from the mirror registerfor the routing means of the first nonmobile network, is completed,under control of the control means, by routing information from thesecond register of the second mobile network.

The above relates to the case in which a terminal, having the firstmobile network as its home network, wants to make use of the secondmobile network. In the inverse situation, in which a terminal having thesecond mobile network as its home network, wants to make use of thefirst mobile network, in the mirror register connected to the routingmeans of the first nonmobile network, a copy of the user profilereceived by the first register of the second mobile network is recorded,and, for routing a call from the first nonmobile network to the firstmobile network making use of the first mobile network, and having thesecond mobile network as its home network, the control means extractrouting information for the routing means of the first nonmobile networkfrom the user profile of the user recorded in the mirror register.

In this case, routing information for the routing means (X) of the firstnonmobile network, extracted from the mirror register (MLR), ispreferably completed by routing information from the second register(VLR) of the first mobile network (KTm).

With the measures according to the invention, it is achieved that if—inboth situations sketched—a mobile terminal makes use of another networkthan its home network (the term “roaming” is then used), a call isrouted directly to said other network and not, as is customary, by wayof its home network.

DESCRIPTION OF THE FIGURES

The operation of the invention is further explained below on the basisof several figures.

FIG. 1 shows the operation of the invention if the nonmobile networkconnected to the home network of said roaming terminal is provided witha mirror register, as the invention proposes.

FIG. 2 shows the operation of the invention if the roaming terminalmakes use of a mobile network whose underlying nonmobile network isprovided with a mirror register.

DETAILED DESCRIPTION OF THE INVENTION

Both figures show a system for mobile telecommunication, comprising afirst network KTm, arranged for mobile telecommunication—the firstmobile network—, connected to a first network KTv arranged for nonmobiletelecommunication ùthe first nonmobile network ùsuitable for setting upconnections between, on the one hand, an (in this case) wirelinedterminal TKTv, whose connections are routed by way of routing means(telephone exchanges, switches, Service Control Points etc.) X withinthe first nonmobile network KTv and, on the other hand (mobile)terminals whose connections ùby way of GSM-network modules, such as MSCs(Mobile Switching Centres), BSCs (Base-Station Controllers) etc. ùarerouted using “Home-Location Registers” (HLR) and “Visitor-LocationRegisters” (VLR) within the first mobile network ù or using similarregisters HLR and VLR within a second network DTm arranged for mobiletelecommunication ùthe second mobile network. In both mobile networks,the respective HLRs contain information relating to mobile terminals ortheir users, as the case may be, with the first or second, as the casemay be, mobile network as its home network; the VLRs contain informationrelating to the mobile terminals or their users, as the case may be, whomake use of the mobile network, irrespective of their home network.

If, as FIG. 1 illustrates, a terminal TKTm having the first mobilenetwork KTm as its home network, wants to make use of the second mobilenetwork DTm, the second register VLR of the second mobile network DTm atits request (“UP?”) receives a user profile UP from the first registerHLR of the first mobile network KTm, comprising system data relating tothe user of said terminal, such as user rights, subscription type etc.

Here, a mirror register MLR, connected to the routing means X in thefirst nonmobile network KTv, receives a copy of the user profile UPgiven off by the first register HLR of the first mobile network, andrecords it.

For routing a call from terminal TKTv to the mobile terminal TKTmroaming near the second mobile network DTm (having the network KTm asits home network), routing information for the routing means X of thefirst nonmobile network is extracted from the user profile UP recordedin the mirror register MLR of the user of said terminal TKTm. Inparticular, the “Mobile Subscriber Roaming number” MSRN is transmittedto the routing means and used there for routing the call thereto.

As represented in the figure, said MSRN is preferably obtained from thesecond register VLR of the second mobile network DTm, mentioningparameters required for that purpose from the user profile, stored inthe mirror register, of the (user of the) roaming mobile terminal TKTm.

FIG. 2 shows the operation of the invention if a roaming terminal TDTmmakes use of the mobile network KTm, whose underlying nonmobile networkKTv is provided with the mirror register MLR. The terminal TDTm has themobile network DTm as its home network. In this case, the secondregister VLR of the mobile network KTm receives, from the first registerHLR of the second mobile network DTm, a user profile UP relating to theuser of said terminal having user data (user parameters). The mirrorregister MLR, connected to the routing means X in the first nonmobilenetwork KTv receives and records, under control of its control means, acopy of the user profile UP given off by the register HLR of the secondmobile network DTm. For routing a call from a terminal TKTv connected tothe nonmobile network KTv to the roaming mobile terminal TDTm ùhavingthe mobile network DTm as its home network ùthe control means extractrouting information for the routing means X in the nonmobile network KTvfrom the user profile recorded in the mirror register MLR of the user ofsaid terminal TDTm.

Said MSRN, as represented in the figure, is preferably obtained from thesecond register VLR of the first mobile network KTm, mentioningparameters required for this purpose from the user profile stored in themirror register of the (user of the) roaming mobile terminal TDTm.

In both cases illustrated in FIGS. 1 and 2, respectively, the inventionimplies the use of a mirror register MLR (Mirror-Location Register) inthe nonmobile network KTv, where a copy of the user profile transferredto the VLR register by the HLR register is recorded. The user profilethus stored in the mirror register MLR is then used to directly drivethe routing means X of the nonmobile network KTv.

It is to be noted that the HLR, the VLR and the MLR, apart from theregister proper, also comprise control means for approaching, exchangingor processing the system information stored in the registers; in thefigures, said functions are drawn as separate entities ùa control “box”and a data-base symbol.

1. System for mobile telecommunication, comprising a first networkarranged for mobile telecommunication (KTm), the first mobile network,connected to a first network arranged for non-mobile telecommunication(KTv), the first non-mobile network, suitable for setting up connectionsbetween, terminals (TKTv) whose connections are routed by way of routingmeans (X) within the first non-mobile network (KTv) and terminals whoseconnections are routed using registers (HLR, VLR) within the firstmobile network or using registers (HLR, VLR) within a second networkarranged for mobile telecommunication (DTm), the second mobile network,wherein, in both networks, a first register (HLR) contains informationrelating to mobile terminals having the first or second mobile networkas their home network, and a second register (VLR) contains informationrelating to mobile terminals that, irrespective of their home network,make use of the first or second mobile network, while, in case A, if aterminal (TKTm) having the first mobile network (KTm) as its homenetwork wants to make use of the second mobile network (DTm), the secondregister (VLR) receives a user profile for the second mobile network(DTm) from the first register (HLR) of the first mobile network (KTm),comprising system data relating to the user of said terminal (TKTm), andwhile, in case B, if a terminal (TDTm) having the second mobile network(DTm) as its home network, wants to make use of the first mobile network(KTm), the second register (VLR) receives a user profile for the firstmobile network (KTm) from the first register (HLR) of the second mobilenetwork (DTm), comprising system data relating to the user of saidterminal (TDTm), characterized by a mirror register, located in thefirst non-mobile network (KTv) and connected to the routing means (X)wherein, under control of control means, a copy of the user profilegiven off by the first register (HLR)-of the first or second mobilenetwork is recorded, while, in case A, when routing a call from thefirst non-mobile network (KTv) to said mobile terminal (TKTm) making useof the second mobile network (DTm) having the first mobile network (KTm)as its home network, the control means extract routing information forthe routing means (X) of the first non-mobile network from the userprofile recorded in the mirror register of the user making use of saidterminal (TKTm), and while, in case B, when routing a call from thefirst non-mobile network (KTv) to said mobile terminal (TDTm) making useof the first mobile network (KTm) having the second mobile network (DTm)as its home network, the control means extract routing information forthe routing means (X) of the first non-mobile network from the userprofile recorded in the mirror register of the user making use of saidterminal (TDTm).
 2. System according to claim 1, characterized in thatrouting information for the routing means (X) of the first non-mobilenetwork, extracted from the mirror register is supplemented, undercontrol of the control means, with routing information from the secondregister (VLR) of the first mobile network, for case B, or of the secondmobile network, for case A.